04 April, 2008

RFP is "request for proposal", a term that's often bandied about in our near-the-beltway town. I'm looking for feedback, proposals, on the BCD to be used on new VO cranks. Since the the comments in the previous post degenerated, or generated, into a discussion of various crank preferences and BCDs I thought this would be the perfect time get into this.

My inbox often contains messages with ideas for new products including cranks. Here are some options that have been suggested.

86bcd, the old Stronglight 99 pattern. The smallest ring possible is 28t. The person who suggested this is a well known frame designer/manufacturer.

50.4bcd, this is the pattern used on TA Pro-5-Vis, Stronglight 49d, Nervar, Sugino PX, etc. It's also the oldest BCD still made. The smallest ring is 26t.

110/74bcd; we all know this one and VO is already sourcing this crank, but using an existing mold to keep cost down. It may have outboard BB bearings! The RFP is for a crank using new molds. And though I like the TA Zephyr we won't make a copy; the Sugina Alpina is close enough.

The old Rene Herse BCD, 3-pin, is a very pretty crank.

94/56bcd. I've never used this size.

I am currently leaning toward using 50.4bcd. It seems to be the most practical; it's very light, allows a low q-factor, looks nice, and takes a huge range of chain rings. The arms can be set up as a single, double, triple, or quad! We would also make VO chainrings in the most popular sizes, 48,46,30,26... This would ensure a supply of rings from two manufacturers. The shape of the arms would loosely resemble the Stronglight 49d. Waddaya think?

In other news, The RH-style roller hangers are done and on the way. The TA/Toei-type water bottle cage is ready for production, based on the latest sample photos. And those 650b fenders should finally be ready.

87 comments:

i vote for a detachable spider ala the excellent middleburn crank, not ala cook r2r cranks, or syncros cranks. shimano used a similar spline, as does white industries. barring that, i think a stronglite copy is smart, but only if its cold forged and polished. the rene herse cranks are super dope, but in reality we need more compatibility with existing equipment rather than something totally new. i would conquer the rene herse cranks when there is nothing left to do.

Chris, I traded in a set of Strong-light 49Ds a couple of years backbecause of the flexibility of theouter TA chainring. Other people, likeJan Heine, do not find this a prob-lem, and these cranksets have be- come popular again. I really like the idea of being able to use the 50.4mm cranks with double chainringsuch as a 30 and 48 because I don'tcare much for triples, but theflexibility issue bothers me. Myvote goes for the 86mm bcd, givinga small chainring of 28, but asJohnson indicates, that could makefor compatibility problems. Myabethe detachable spider is best. PG

I've been using TA Pro 5 Vis for donkey's years, and what I have always wanted to see were options to use those cranks with other chainrings. I have a Williams adapter for running 151 BCD, but it seems no one has made adapters for other BCDs. It should be easy enough to have a series of adapters for 110/74, 86, and larger sizes.

A BCD smaller than that may cause interference issues with the 50.4 BCD of the crank itself.

This way you can satisfy a bunch of people with only one crank mold, and a bunch of different adapters.

Or have a series of outer chainrings that take different BCD inner chainrings, I once saw an Eggring for TA cranks with 110 and 74 BCD mounts, again, easy enough to have them made with other BCD mounts.

By the way, I have a bunch of TA 19tooth chainrings (50.4BCD) that bolt straight to the cranks, even more options!

you can set up a 110/74 to be a wide range double, you just get none of the advantages of a dedicated wide double system: clean looks, low q. but: move the big ring to the middle position, and run a granny in the 74 spot. ugly, but there it is. i've run it, works fine.

I am strongly in favour of 50.4. 110/74 is well covered and the other options are obsolete in terms of chainrings with little evidence of a resurgence. Availability of the TA crank arms is variable with the possibility that they may cease production any time (if not already). VO should carry the torch on this one. I think it's a product very much in keeping with the spirit of V/O

I vote for whatever allows a wide range double set-up, looks good and costs the least for the consumer. I can't afford $250 cranksets, even if rings are included. The 50 sounds great but if for some reason the 86 or 94 is $75 bucks cheaper, I'd prefer the less expensive set.I'd love to see a production wide-range double at Sugino prices.nv

I noticed that for a while in the 1990's we saw some pretty good looking CNC type cranks. Yes Cook Bros. was one of the most popular. All of a sudden it seems CNC'd parts in general seemingly dried up. I'm not too sure if the crank offerings from Paul or White Industries are CNC or not. But they seemed to have quite a few followers at the handmade bike show in Portland.

I'm guessing in smaller quantities it would be easier to make a CNC crank. I would assume forging requires more start up costs. But it just seems the quality of the aluminum and the process should be an important consideration.

As far as BCD I like the standards in place such as 130, 110/74, and even 144 for track. However for road use it's hard to knock 130. Plus it's easy to find high quality TA rings in 130.

And that is another consideration is the quality of the chainring. All I know is that TA's rings last longer and perform better than any I've ever tried in my nearly 35 years of almost every day bicycling.

When I first started serious cycling in the early 1970's I couldn't afford Campy so I always opted for Sugino instead. They turned out to be very good over the years. But when I got a 1974 Motobecane Grand Record that had the 3-arm TA pro cranks ... I am simply amazed at the durability of those rings. They simply don't wear out. Over the last several years when putting together a new bike I always try and find the TA rings. And the polish and fit on them seems to be as good as any out there. And most would consider them the gold standard.

So when it comes to chainrings it's hard to build a better ring than TA ... at least IMHO.

But getting back to cranks ... if you decide to reproduce some grand styles of the old Stronglight, TA, or Nervar persuasion please do quality job. Nice pretty cranks should last over forever. And good ones are just plain cool.

Also one more thing. Make sure and offer them in shorter lengths such as 165. It's hard to find lengths shorter than 170. And I've noticed using the shorter arms is easier on the older knees.

Oh one more thing...yes the bottom bracket configuration. Square taper is still the classic. The Tange $30 BB works pretty well for the money and of course one can't top the Phil bottom bracket. I don't see the need for the new high production outside bearings cranks. These are seemingly designed to be sold and manufactured for the me too racing crowd who love to show off their snazzy racing costumes on the weekends while riding their 14 lb. carbon racing bikes in the wanna be Tour de France along our local Southern California roads. No reason to enter that market in my opinion. Stay focused on the classic cyclists who are starting to have a hard time finding classic parts.

Chriscullum ...True about the CNC cranks back in the day of the upstart CNC revolution. But it seems the newer CNC are quite nice and now that there is more knowledge on the right materials plus CNC machines are much cheaper to buy than they were back 20 years ago. It just seems the reverse might be true today.

Another vote 50.4bcd! I'd definitely buy a VO version. I love my Sugino PX. Also, it would be nice to have a another source for rings besides TA. I'll buy a Herse-style crank if you make them, but if you can only do one, make it 50.4.

My vote would be be for 110 bcd for forward compatability with the super broad spectrum of ta cyclotourist rings... Since I'm already heavily invested in the 110 bcd, of course I'd like to see a vendor like VO support this format (since I'm already dependent on you for my future ta cyclotourist replacment rings).

94 BCD! Rings down to 31 are easy to find. Suntour, Ritchey (probably Sugino), and TA (Berthoud shows a 94 BCD Zephyr) have all made excellent 94/xx triples. For me 2x7+ is ideal for most brevet riding, so I'd vote for a 94 BCD double with a nice narrow tread and square tapers. Sugino most have a mold.

It was my understanding that cold forging densifies and imparts a "grain" to the Al making it stronger. I'm not sure how CNC machining billet Al can be as strong but maybe new alloys or techniques achieve better results. If CNC is at least as strong as forged and cheaper to produce I'm all for it.

I have a suggestion--128, to fit the old Nervar Star. No one makes them any more, and I would rather try to persuade someone to pour thousands of dollars into making a new product so I don't have to abandon this flexy old crank in favour of any number of viable alternatives.Jokingly, M Burdge

In the article, Chris states "I like the TA Zephyr we won't make a copy; the Sugina Alpina is close enough."

Interesting. I'm in the market for a compact double with square taper. I found one Sugino Alpina/Cospea at $265-295 (depending on what rings you want) at Jitensha. It is more than I can afford.

I then found something called a Sugino Alpina 2 crank with square taper that sells for about $115. The main difference besides the logo are the rings. The Alpina 2 rings looks like a stamped cheap chainring.

If Chris is talking about the Alpina/Cospea "1," is there a place that sells them for less than $300?! Thanks.

50.4 clearly. What other pattern provides as much choice in chainring options? The 86mm Stronglight pattern is quite nice but doesn't suit as many legacy rings: BSA, Cyclo, TA, Stronglight, Nervar and many other rings were made to this pattern.

110 cranks are a dime-a-dozen, I don't see a need there. I wouldn't mind a 94bcd, I use one currently as a 46/30 double, but I think the 50.4 is the way to go. Rings from 19t up to 60-something! Hard to beat.

definitely resurrect TA style 50.4 bcd crank. The cranks seem lighter and look nicer than mid 80s and current 110/74 bcd cranks. Certainly nicer than current crop of road and dirt cranks. Make them with standard allen bolt fixtures, standard tapers, you have a winner.

Any BCD below the current 110 is fine. My Centaur compact double crank is currently setup as a single-speed, using a 34-tooth chainring. Even that ring is too big (yes, I'm the world's slowest cyclist...). I'd prefer something like a 29 tooth.

A couple of thoughts: Our chain rings will be CNC cut, so we can make them thicker or even have ribs to ensure that they are stiff enough. I don't think the old 50.4bcd stiffness issue, or non-issue is worth considering. And stiffness is only a problem in rings over 50t.

Regarding the Alpina Octalink crank, some in the industry think this is a dead BB standard and are blowing out their remaining stock before everyone else does. I don't know enough about it to have an opinion.

We are committed to have a forged VO crank, but we might try a small run of CNC cranks first to try out a few ideas before we commit to paying for molds. Crank molds are very expensive.

I vote for the 50.4, because the current TA is kinda pricey and availability limited. As as single or wide range double, it is aesthetically beautiful. As a triple, it is cluttered, and I would prefer the Sugino not only aesthetically but also for cost. If you came out with a TA copy, I would especially buy it if a smaller outer chainring was available, like 36t, or I suppose even 38t. Living in Chicago, I would run it as a single, and then add the granny gear if I were to be in the hills. Otherwise I will buy a Sugino triple and use the only the middle gear with a cyclocross spacer in the outer ring, sans derailleaur Thanks! excited about this project. p.s. I would pay up to $150 for a double crank set up.

I think that the outer 130/inner 74 idea sounds ingenious. Easy to source rings, and an incredible basis for a wide range double. Of course unlike the 50.4, it would be impossible to use the same arms for a single, double, triple, or quad. Well, while TA is still making Cyclotouristes, a 130/74 would really be a VO exclusive.

For all those crowing about a 110 or some other bolt pattern: why not just get an old sugino set? They are a dime a dozen at most second hand bike shops. An inexpensive 50.4, on the other hand, does not exist. Plus it would be great to have another source for chainrings.

50.4 gets my vote. I've been grabbing every pair of short (160) pro 5 vis that I can find on ebay because they are such a fantastic crank. I actually think they looks better than the RH cranks, which look a bit chunky to me.

Sometimes things are refined to perfection long ago and people try to do better without much luck.

50.4 would be nice. Nicer still would be a couple of minor updates on the original - a little more room twixt crank and chainring for more modern derailers (we'll miss you, Sheldon) and ribs on the outside rings to stiffen them for use on wide range doubles.

Of course in a perfect world they'd be made in a variety of lengths as well but if that's not feasible then I'd suggest ignoring the 170 -> 175 market that's already saturated and concentrate on the 160 -> 167.5 and 180+ that are so rare these days.

I would also go with an existing standard: 50.4 or 94.Due to the poularity of compact doubles the 110 standard is pretty well covered by others. Because of 1 tooth (28 vs. 29) i wouldn't go with the obsolete 86 over the 94. The big advantage with 94 over the 50.4 would be the option to change rings with the crank mounted. Also they make the best looking Mountain (42/29) doubles. Whatever it is: low Q-factor! Make the triple mount on a 120 or wider spindle, so one can reduce the Q-factor for use as a double. Shimano's 94 cranks often mounted on 107 spindles, so there is no way to reduce spindle length for double application.

I like the 50.4 TA style crank idea a lot. I have a good collection of rings, there are plenty of rings available, and adaptors for other patterns would be cheap and easy to make. Just a simple waterjet cut plate could work for lots of different configurations, depending on the exact configuration of the right arm. A reliable source for the crankarms at a reasonable price would be wonderful. I use 180mm cranks whenever I can find them, and I love them, too. I'd like to try a pair of 185s.

what's this move towards massive cranks? if the bb is at the right height, long cranks are knuckle draggers. if you are riding a single speed, off road, and you have a high bb, and you live in a really hilly area, and you ride a tall gear, maybe they make sense. but for road use?

there is a decent amount of data that shows that longer cranks are A. worse for your knees, B. less efficent. is there new data? has leonard zinn been usurped?

185s? that's bmx racing length. and even there they dont make much sense. there is a reason you dont see too many track cranks in 180- they arnt good for spinning, or pedaling thru turns. further, extra long cranks mean that you either need a whole new mold (165-175 can use one mold) or that the short cranks have a ton of extra material. part of the reason sugino took TA's buisness away in the early 80s was that TA was unwilling to produce new molds for the 180mm crank, even though demand was high. i've ridden multiple length cranks back to back for long miles, on and off road, single speed and multispeed. the difference between 175-165 is neglible, but 180s actively scrap the ground around corners, clip rocks off road, and hurt your knees if you are spinning quickly. now, they might not hurt people's knees with longer legs, but everything else holds true.

there is a reason the 'market' for 165-175 cranks is saturated. history has proven these lengths to be the best compromise of leverage and um, spinnability. if 150mm or 185 cranks were more efficent, by say, .25 watts, dont you think that say, TT bikes would have them?

Regarding the crank lengths - different strokes. I don't know that I'd say the 165mm market is saturated - the last time I checked it was fairly bleak, just not as bad as the 180+ or 160 and below market.

I'd say that that the reason that the market is centered on the 170 to 175 lengths is that those lengths work well for normal sized males trying to produce the most power in racing conditions. That's good, but it doesn't feel like quite the target audience for Velo ORANGE. Now, if it's easy to have a variety of lengths then by all means, keep the saturated lengths!

Nice, clean square-ish profile though one that extends out a bit from the BB for those of us who pedal ankles in and are tired of our ankles rubbing our cranks.

28, 30, 32, 34, 46, 48, 50 rings. The larger rings should be thicker or reinforced in some manner so they don't flex as much as the old TA rings. Rings should be well polished so as not get dingy the way cheaper Sugino rings do.

Square taper since the crowd you're targeting seem to freak out about anything else.

Cold forged. A little more stout than the TA since there are plenty of people who seem to complain about this. That many people can't be wrong and I've seen my share of TA cranks go bust.

Ideally, keep the price reasonable. Cranks with rings should come in at $250 or less. Campy can produce a very nice Centaur compact that retails for under $200.

If a decision between 58/94 and 50.4 bcd cranks has to be made, then we all know where VO lean towards.

Octalink and ISIS interface cranks definitly solved a problem with produciton bikes (and even the high end racy enthusiast types( left cranks falling off. But it brought out another problem, that of premature BB bearing wear. you could get thousands of miles from the UN52 or UN72 BB's but Octalink or anything with an ISIS spline you'd be lucky to get a couple thousand before replacement. That's why outboard bearings became popular. And attaching the arm to the spindle was a way to reduce weight, increase stiffness, and keep chainline issues minimized. Now, FSA is pushing their new BB30 design, and have a decent number of Manufacturers (Specialized, Cannonmdale) and even some smaller builders on board with the standard.

So, maybe there is a place for a 50.4 BCD with integrated spindle......and a BB30 outboard bearing.....??...I'll duck now.....

Despite my crack yesterday, I continue to hold an affection for the old Specialized 'flag' cranksets of the 80s/early90s. Low Q, 110/74 (=ring availability), forged, attractive. Their only drawback, I suppose, is they don't look like old French cranks. But then I am 36, not mid 50s, so my aesthetic mold is set in a different era.m burdge

I really didn't expect to even notice any difference the first time I tried some 180mm cranks, but I did, and I like them, and they work great for me. I am very glad I didn't just believe what I read about them, and actually *tried* them. I have one set on a road bike, and three on mountain bikes. One of the mountain bikes is a single speed. Yeah, I scrape pedals on rocks and pavement a bit more often, but so what? I don't waste my time telling other tall guys they should be using them, simply because I could be very wrong. They might hate them. Same goes for tread. After reading a lot of the Rivendell bits about Q factor, I worried about it for a while and finally got a fixed gear set up with a tread of 140mm or so. Guess what? It was very uncomfortable, and caused a lot of stress on the outsides of my feet. It is my good fortune that over the past 20 years or so, average tread has increased by an inch or more, but I don't tell others that wider is better. That would be foolish.

Several comments suggest clusters of ring sizes at the lower and higher end. I'd prefer to see rings in the even numbers going from 28 to 50. I like an outer ring of 36, 38, 40 or 42 depending on the application of the bike it's on. Having a big gap in ring offering from mid 30's to mid 40's would be a bummer.

Is the 50.4 doable with the outboard bearing big tube axle design? Hmmmm. If the ring or adaptor went on from "behind" or over the bb spindle, that could work very well with some spacers to make all sorts of adaptors possible, as well as zeroing in chainline or tread. Or no spacers for certain set ups. Like the TA Pro V and its clones, there would be a complicated assortment of fasteners involved with most arrangements, but that's a small price for all that versatility.

50.4? Who sells rings for that size? Aren't you guys limiting your self to one supplier?

Sorry, nothing against V-O, but this is sort of like Campy limiting its cranks to only to chainrings with its 135bcd and/or 110/112 "compact" bolt pattern.

Others have stated that there are already enough 110bcd cranks on the market. I say that other than the hard to find square taper Sugino Alpina/Cospea, which also cost a ton ($300+), what else is out there? Alternatively, would V-O or someone else consider selling the square taper Sugino Alpina/Cospea (not the Alpina 2 sold by some with low-grade rings for about $110).

Btw, for those of you needing lower gearing than a 34t, why not just get yourself a triple! Good Luck!

Anon above - There are lots of 110/74 cranks available. Sugino, Shimano, Stronglight, FSA, Nashbar, Origin 8, Truvativ, etc offer 100/74 - and thats off the top of my head - I'm sure there are more - possibly many more. Plus, the chainrings are easy and relatively inexpensive to source. Plus plus, do a search on eBay on any given day and you're likely to find 100+ 110/74 cranksets - both new and used. Many very nice and many very inexpensive - and sometimes both. If VO produces 50.4 chainrings at normal VO pricing, I don't think it matters if anybody else has 50.4 rings.I see no use in bringing another 110/74 crankset to market. The obvious void in current crank offerings is the wide range (or in my case, the low-range) double. Go Chris! I hope this project is as awesome as it sounds!nv

To all those who worry about too narrow a Q factor; try pedal spacers. They work just fine.Chris should make a crank with a reasonably narrow Q and let those who have problems with that use spacers. You can't make a high Q crank narrower.

I am not a fan of low q. I tried it recently, a pre-boom cottered steel crank, and found it uncomfortable and inefficient for a larger rider my size. Still, go ahead - not that you need my permission :). There are plenty of choices of wider cranks on the market. I guess I'm leaving this comment to suggest that readers of a (desevedly) very convincing journalist should not take low q to be an absolute design objective but a personal preference that will vary with the rider, probably with his or her size. There are good cranks out there now. To attract me away from a mass produced group, I'd be looking for a combination of wide choice in chair rings, reasonable price, and aesthetics.

I've never met a Q I didn't like ;)Seriously, I can't tell the difference between the 15 or so different cranksets I've ridden over the last 10 years. I guess if you count bike rentals and friends bikes, that number would double. That said, I've never ridden TA cranks so it's possible I've never been on a truly low Q crankset - I never bothered to measure any of my own because they all go round and round and they all felt fine to me.nv

Make adapteurs for other normal sizes, like 110/74, but make them offset so one can use them on TA cranks with modern front derailers.

Large length selection, at least 160 to 180mm.

Long cranks work for me. I'm not sure I understand the vitriol about it. If you like short cranks, use them. If you're striking pedals, your bb is NOT at the right height. By the way, Zinn has rescinded his original testing that proved super short cranks more efficient. Read through this page: http://www.zinncycles.com/cranks.aspx

Also, please simplify the hardware, but make it compatible with TA. What are there, about 839 separate bolts, nuts, washers, and spacers in a TA triple? OK, I'm exaggerating, but not by much.

Somebody please explain to me what advantage a 130/74 double would have over a 110/74 double? Aesthetic? I don't get it. If you are looking for a wide range double, I doubt you would want much bigger than a 50 tooth ring. A 50 works fine on 110 (and looks fine, too IMO)

"I've seen lots of Octalink BBs that have well in excess of 2,000 miles on them."

My Octalink b/b has around 1200 miles on it. The Ultegra Octalink b/b is the one I like most of all, and mine is still as smooth as the day I bought it. The key I've found with Octalink is to carefully line up the spline interface between the crank and b/b before tightening it up, and after you've ride on it a while check the tightness of the unit from time to time. The Dura Ace Octalink b/b has adjustment rings on both sides and many users reported frustration with that one even if they were a competent wrencher. All in all I'm happiest with good old square taper b/b's.I've rode friends outboard bearing b/b's, but I can't tell any differences - then again I'm a light rider.

It's got to be 86bcd! O.K. I admit to being a huge Stronglight 99 fan.But there is much to like, down to 28t, can be single, double or triple, 5 bolt support for rings. How about 165-180 arm lengths and full polish classic good looks.

"You will have to come up with something very special to beat the TA Carmina"

I didn't know this was a competition! ;)I would have to respectfully disagree with the above statement. IMO, the Carmina is ugly - arms are much too broad and the contrasting spider - why!?Also, $400 for a crankset? I wish I could afford that! I'd take a $75 Sugino any day.Make a nice, polished silver, wide range double with elegant arms and make the rings readily available. Sell it for half as much as the Carmina. How would this not beat the pants off of the TA? You'd have to be an absolute hardcore Francophile to choose the latter.

"94 BCD! Rings down to 31 are easy to find. Suntour, Ritchey (probably Sugino), and TA (Berthoud shows a 94 BCD Zephyr) have all made excellent 94/xx triples. For me 2x7+ is ideal for most brevet riding, so I'd vote for a 94 BCD double with a nice narrow tread and square tapers. Sugino must have a mold."

Ditto on the above comment posted by Andrew. I have no objection to ordering from Velo Orange, but would prefer to be able to find chainrings from a variety of sources.

Maybe I'm a frickin' oddball, but it makes good sense to me to make a crank based on the very popular old TA Pro 5 or whatever the precise nomenclature is, and sell those and lots of rings too. As far as having rings made, bolt pattern choice does not affect the cost per ring to any great extent. Cranks can outlast several sets of rings, so there have to be lots of cranksets out there that would be fine for another couple of decades if there were rings available. As far as any of the recent mountain bike standard patterns go, well, what was the point of that again?

Thank you for all your comments and thoughts. 50.4bcd wins!. A sample crank is already speeding toward our secret factory in Taiwan. I sent a Nervar crank because it has close the ideal geometry, low Q factor with a bit more room between the arm and the big chainring. Of course we will change the fluting and the dimensions of the arms.

Regarding Sugino Alpina cranksets. I learned that there are four quality levels of chain rings available on Alpina cranks. The very best are CNC machined, pinned, ramped, and close to TA quality. There is a huge price difference depending on the rings you choose.

I would urge that you produce the 50.4mm crank-- I shudder to think of life without my collection of TA Pro Vis 185mm crankarms! Thus, I really would love to see you produce more new 185mm arms. Sure, I'm 6'6", but there are more of us out here than it may seem.

I'm a big fan of my Carmina double with 94 BCD. Running it currently with a 30/42 on a Phil BB. Late in the season (or when I'm not lugging the trailer and gear) I swap the rings to a 32/46 or a 32/48. I've run it as a 'compact' 34/50 as well, but prefer the low end here in VT. I'm running a Campy 10 sp 13-29 in the rear. I spent the $$ on a bunch of different rings - so I have options to tune the bike to the ride... rather than have a standard 'triple' and never really use the high end, and get frustrated with the low end.

I really like the low Q - and notice it when switching to my old (wife's) Ultegra triple, or my MTB, or my cargo bike.

I imagine there are many people who are quite happy with existing triples from Sugino and Shimano and who wouldn't spend any money on anything less common unless it was really pretty, like a Herse crank.

I would suggest either 86BCD or the Stronglight 49D which you list as 50.4BCD but is really different since the large chainwheel attaches directly to the crank arm.

I see an advantage for the 86BCD since it would not require as strong a large chain wheel. Also, since there currently isn't a crank set with this BCD in production, you could also sell some chainrings.

With the 49D style crank, the largest is what actually determines the BCD for the inner chainrings. This has both advantages and disadvantages. You can have options for different BCDs for the inner chainwheels. This means more different parts but the only difference is going to be the location of 5 holes. And, if you start with a large BCD, the middle chainring is going to have to also have a smaller BCD for the granny chainring -- this probably isn't going to be just a matter of drilling holes.

It could also be possible to simply do both by offering a 49D style crank set along with a spider for 86BCD chainrings. Would this be significantly heaver than making a one piece 86BCD crank.

If you went with the spider idea, you could offer other BCD spiders as well -- at least the popular 110/74. Perhaps a solution to the large number of different sizes of chainrings.

Also an other question. Will you offer the old style of crank arms that look like a Stronglight 99 or 49D? They do look better on old bikes.

Old bikes also look better with the separate spider and the 49D style with a spider would accomplish this.

How many here have used a TA crank with the 50.4 BCD? I tired them in a 185mm a few years ago, but returned them due to the flex of the arms and rings. The rings would always rub on the front dérailleur. I've never seen a crank flex so much. I'm no masher either, just tall.... about 165 lbs.

I went to a TA Zephyr, and it's rock solid...... Too bad they don't make it anymore.

I'm going to need a new crank soon... and would like a similar tread(Q). I've read varying reports of the Sugino XD arms as far as what their tread is.... anywhere from 160 to 169. The Zehpyr's are about 156mm for the triple.

Has anyone measured the XD triple arms with a 110 BB? I see the Alpina double is listed here in VO as 160mm with a 110BB, but are the XD arms the same ?

Another vote for the 50.4 BCD, with the caveat that the outer chainring attach to the others with both the options of the traditional TA 6-bolt pattern, and in a 5 bolt pattern of variable diameter, like the White Industries crank.

Another vote for the 50.4 BCD, with the caveat that the outer chainring attach to the others with both the options of the traditional TA 6-bolt pattern, and in a 5 bolt pattern of variable diameter, like the White Industries crank.

Nothing beats a TA Carmina for length and BCD options. You don't have to have a contrasting spider. If you used a interchangeable spider, then you can offer different BCD's. Sugino has limited lengths and wide Q, and tall riders should not be using 175's. It's a joke the expect them to. Debate over.

Why not make a Stronglight-49 pattern 50.4 adapter, one that goes out to 130 bcd (like the Williams chainring adapter)?? Then we could have the best of both worlds. People with TA or Sugino 50.4 cranks could get the stronglight 49/93 look, using old Shimano Dura Ace or Takagi BMX rings from Japan.